TECHNOLOGICAL IMPROVEMENT ON MANUFACTURE OF HIGH-PRECISION SMALL-SIZED SEAMLESS STEEL TUBES & PIPES

Based on the shortcomings of the conventional cold-drawing process using larger sized pipe as stock to produce small high-precision seamless steel pipe with W.T obtained through the first pass,a new cold-drawing process has been introduced,which uses smaller pipes as stock to produce the said high-precision pipe with W.T obtained though the first pass.Accordingly the respective modified plug employed by the new process is described.It is concluded that the related operation practice has proven the new process is capable of producing high-precision small sized tubes and pipes with both geometric tolerances and surface quality satisfactory to related technical criteria.